Conventionally, there has been known a technology for recording image information drawn on an object, such as a whiteboard or a blackboard used in a meeting, a lecture, and the like, as a video. However, on a simply-shot video of the object, a moving body, such as a person who draws image information on the object, is captured, thus, when the drawn image information is obstructed by the moving body, the visibility of the image information is degraded.
For resolving such degradation of the visibility of the image information, there has been developed a technology for extracting contents written on a blackboard as an object from a blackboard video obtained by recording a video of the blackboard, in such a manner that a content area where addition or deletion of contents is made is periodically being extracted from the blackboard video, and line-detecting the contents from the extracted content area, and then vector data is generated as image information (for example, see Patent document 1: Japanese Patent Application Laid-open No. 2006-162692).
However, in the above conventional technology, the entire range of areas where a lecturer area is moved in a certain period of time is extracted from the blackboard area and held, and an area that the lecturer area of a current frame is removed from the range is set down as a search area to be searched for update information on characters written on the blackboard, thus there is a problem that, for example, if the lecturer area is not moved over a long time, a detection time of characters written on the blackboard, i.e., image information lags significantly behind a time when the image information is actually drawn.
The present invention has been made to solve the above problems, and an object of the present invention is to provide a video editing device capable of suppressing a delay of a detection time with respect to a time when image information is drawn at the time of extracting the image information from a video of an object.